Consider the following classifications:

grizzly bear: Ursus arctos

polar bear: Ursus maritimus

What do the scientific names of the grizzly and polar bears tell about their similarity to each other?

Binomial nomenclature is a formal system of naming species. In this nomenclature, the first word indicates the organism's genus classification, the second word indicates the species within a genus.

So, the grizzly and polar bears have the common first word. So they belong to the same genus. However, their second word is different, hence, they are different species within the same genus.